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It has recently been shown within a formal axiomatic framework using a definition of four-momentum based on the St\"uckelberg-Feynman-Sudarshan-Recami "switching principle" that Einstein's relativistic dynamics is logically consistent with…

General Relativity and Quantum Cosmology · Physics 2014-01-14 Judit X. Madarász , Mike Stannett , Gergely Székely

Knowing when a physical system has reached sufficient size for its macroscopic properties to be well described by many-body theory is difficult. We investigate the crossover from few to many-body physics by studying quasi one-dimensional…

Quantum Gases · Physics 2013-10-28 A. N. Wenz , G. Zürn , S. Murmann , I. Brouzos , T. Lompe , S. Jochim

The concept of entropy in nonequilibrium macroscopic systems is investigated in the light of an extended equation of motion for the density matrix obtained in a previous study. It is found that a time-dependent information entropy can be…

Statistical Mechanics · Physics 2009-11-10 W. T. Grandy

A time dependent variational approach is considered to derive the equations of movement for the $\lambda \phi^4$ model. The temporal evolution of the model is performed numerically in the frame of the Gaussian approximation in a lattice of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Fabio L. Braghin

This paper focuses on a class of nonlinear Klein-Gordon equations in three dimensions, which are Hamiltonian perturbations of the linear Klein-Gordon equation with potential. The unperturbed dynamical system has a bound state with frequency…

Analysis of PDEs · Mathematics 2022-09-22 Zhen Lei , Jie Liu , Zhaojie Yang

Time evolution of quantum systems is accelerated by the fast-forward scaling. We reformulate the method to study systems in a finite-dimensional Hilbert space. For several simple systems, we explicitly construct the acceleration potential.…

Quantum Physics · Physics 2014-04-24 Kazutaka Takahashi

An important and incompletely answered question is whether a closed quantum system of many interacting particles can be localized by disorder. The time evolution of simple (unentangled) initial states is studied numerically for a system of…

Strongly Correlated Electrons · Physics 2012-07-11 Jens H. Bardarson , Frank Pollmann , Joel E. Moore

Many applications require that we learn the parameters of a model from data. EM is a method used to learn the parameters of probabilistic models for which the data for some of the variables in the models is either missing or hidden. There…

Machine Learning · Computer Science 2013-01-30 Luis E. Ortiz , Leslie Pack Kaelbling

It is shown that it is possible to bosonize fermions in any number of dimensions using the hydrodynamic variables, namely the velocity potential and density. The slow part of the Fermi field is defined irrespective of dimensionality and the…

Strongly Correlated Electrons · Physics 2009-11-11 Girish S. Setlur

The paramagnetic phase of heavy fermion systems is investigated, using a non-perturbative local moment approach to the asymmetric periodic Anderson model within the framework of dynamical mean field theory. The natural focus is on the…

Strongly Correlated Electrons · Physics 2009-11-11 David E Logan , N S Vidhyadhiraja

We present a unitary framework for dissipative quantum dynamics that can be efficiently applied to large-scale Fermi systems. The method introduces local Hermitian operators that emulate frictional forces while strictly preserving the…

Nuclear Theory · Physics 2025-12-16 J. E. Alba-Arroyo , Daniel Pęcak , Michael McNeil Forbes , Gabriel Wlazłowski

We consider translation invariant quantum systems in thermodynamic limit. We argue that their energy-momentum spectra should have shapes consistent with effective models involving quasiparticles. Our main example is second quantized…

Mathematical Physics · Physics 2012-06-04 Jan Dereziński , Krzysztof A. Meissner , Marcin Napiórkowski

The search for constituents that can explain the periods of accelerating expansion of the Universe is a fundamental topic in cosmology. In this context, we investigate how fermionic fields minimally and non-minimally coupled with the…

General Relativity and Quantum Cosmology · Physics 2014-12-23 Guilherme Grams , Rudinei C. de Souza , Gilberto M. Kremer

In sustained growth with random dynamics stationary distributions can exist without detailed balance. This suggests thermodynamical behavior in fast growing complex systems. In order to model such phenomena we apply both a discrete and a…

Statistical Mechanics · Physics 2017-03-22 Tamás Biró , Zoltán Néda

Fermi bubbles are giant gamma-ray structures extended north and south of the Galactic center with characteristic sizes of order of 10 kpc recently discovered by Fermi Large Area Telescope. Good correlation between radio and gamma-ray…

Astrophysics of Galaxies · Physics 2015-06-23 D. O. Chernyshov , K. S. Cheng , V. A. Dogiel , C. M. Ko

We present a proof of the monotonic entropy growth for a nonlinear discrete-time model of a random market. This model, based on binary collisions, also may be viewed as a particular case of Ulam's redistribution of energy problem. We…

Statistical Mechanics · Physics 2013-03-14 S. M. Apenko

There is no single mechanism by which fast particles are accelerated in astrophysical environments, and it is now recognized that the data require a rich variety of different mechanisms operating under different conditions. The mechanisms…

High Energy Astrophysical Phenomena · Physics 2011-07-15 Elisabete M. de Gouveia Dal Pino , Grzegorz Kowal , Alex Lazarian , Reinaldo Santos-Lima

A metric-field approach to gravitation is presented. It is based on an idea of dependency of space-time properties on measuring instruments. Some bimetric equations that realize this idea are considered. They were tested by the binary…

General Relativity and Quantum Cosmology · Physics 2009-11-07 L. V. Verozub

We investigate the problem of backscattering off a time-dependent and spatially extended barrier in a one-dimensional electron gas. By performing a perturbative expansion in the backscattering amplitude, we compute the total energy density…

Other Condensed Matter · Physics 2009-11-11 Carlos M. Naón , Mariano J. Salvay

Shear flows are ubiquitously present in space and astrophysical plasmas. This paper highlights the central idea of the non-thermal acceleration of charged particles in shearing flows and reviews some of the recent developments. Topics…

High Energy Astrophysical Phenomena · Physics 2019-09-17 Frank M. Rieger